Chicago Marathon
Race Day Weather
Mild temps, shifting winds
Runners will face mild temperatures starting at 57°F and peaking at 62°F. A light headwind will challenge them during several segments, particularly from Miles 2, 9, and 18 to 23, while a tailwind aids in the early and late stages. With humidity at 71%, it’s advisable to hydrate frequently and consider adjusting pace during the tougher headwind sections.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
